CAJ | 학술논문

针对交流激励式电容测量电路抗干扰能力差及测量精度受激励源稳定性影响的问题，提出了一种前级加反馈的电容测量电路设计。首先，将传感器输出电压引出，乘以合适的倍数，加到初始激励源。然后，利用模拟乘法器和低通滤波器进行检波。最后，用八位半数字表3458A采集测量结果。实验结果表明，该系统在0～650μm范围内分辨率达30 nm ，电路测量最大偏差为20 nm ，示值稳定性0．1 mV／30 min。该系统满足电容测微系统稳定性好、准确性高的要求。
침대교류격려식전용측량전로항간우능력차급측량정도수격려원은정성영향적문제，제출료일충전급가반궤적전용측량전로설계。수선，장전감기수출전압인출，승이합괄적배수，가도초시격려원。연후，이용모의승법기화저통려파기진행검파。최후，용팔위반수자표3458A채집측량결과。실험결과표명，해계통재0～650μm범위내분변솔체30 nm ，전로측량최대편차위20 nm ，시치은정성0．1 mV／30 min。해계통만족전용측미계통은정성호、준학성고적요구。
For the problem of AC excitation capacitance measurement circuit ’s weak ability of anti‐interference and the measurement accuracy is affected by the excitation source stability ,w e propose a pre‐plus feedback capacitance measure‐ment circuit design .First ,the output voltage of the sensor lead is multiplied by the appropriate factor ,added to the ini‐tial excitation .Secondly ,the system uses the analog multiplier and the low‐pass filter for detection .Finally ,use eight and a half meter 3458A digital capture measurements .The test results show that the system in the range of 0~650 μm resolution of 30 nm ,circuit measures the maximum deviation of 20 nm ,showing the value of stability 0 .1 mV/30 min . The system meets the capacitance micrometer good system stability ,high accuracy requirements .